Recovering of heavy metal concentrates has taken a wide variety of forms. Even recovery of gold concentrates has taken a wide variety of forms ranging from the individual miners panning, or washing ore material from the more dense gold concentrate, and allowing the concentrate to appear in visible form in sluice pans or the like. These gold colored nuggets then were recovered by the miners. On the other hand, a variety of types of gold recovery have employed sophisticated mining from hydraulic mining in which the high pressure liquid was used to mine the ore material and to separate the lighter sand, dirt and the like from the more dense concentrate. On the other hand, certain offshore gold was recovered by large wheeled vehicles which suctioned the sedimentary material from the bottom of the shallow coastal region onto sluice boxes or the like where the lighter material was washed from the heavy metal concentrate and the heavy metal concentrate thereafter processed to recover the heavy metal, such as gold.
Only recently has the inventor of this invention added to these conventional techniques the use of a vibrating screen which has been found to be particularly satisfactory in facilitating recovery of the heavy metal concentrate.
In the prior art methods for recovering the heavy metal concentrate, such as the gold concentrate, has been the requirement that the gold concentrate collector, such as the bottom of the sluice box, has to be cleaned to remove therefrom the interfering material; such as sand, silt and the like; and recover the gold concentrate. This cleaning of the collector for the gold concentrate and returning to service of the sluice box has taken up to fifty percent of the time that the apparatus was used for recovering the heavy metal concentrate. It is desirable that some form of alleviating this problem be provided but the prior art has failed to do so.
Surprisingly, it has been found necessary to recirculate the water to keep from losing fine gold particles when the process of this invention is employed.